Attic granary interior tie rod detail on north gable (east segment)

Iron tie rods were added in the 20th century as restraints against roof thrust acting on the eaves wall plates [“rafter plates”]. This pair in the north gable are secured by threaded nuts on the exterior face of the wall plates, and by embedding the interior terminals in mortar joints [seen to the left in this photo]. These interior rods apparently replaced an exterior rod [see DTHPH7--1001.01.029] which undoubtedly became ineffective because of the deterioration of the exposed end-grain of the wall plate securing the rod spanning the north gable at the eaves level. The gray mortar at the anchor-point is essentially modern “Portland” cement, not a traditional lime-sand or lime-clay mix which would have been applied in the earlier periods of the building. Laurence Ward, 2009